Process for the classifying and separation of solid bodies by combined action of orientation, deviation, and derivation



R. E. TROTTIER. PROCESS FOR THE CL A SSIFYING AND SEPARATION OF SOLID BODIES BY COMBINED ACTION OF ORIENTATION, DEVIATION, AND DERIVATION. APPLICATION nuo NOV. 21. 1911.

1,400,389, Patented Dec. 13, 1921.

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UNITED STATES PATENT OFFICE.

RENE EMILE TROTTIER, OFF IUTEAUX, FRANCE,

PROCESS FOR THE GLASSIFYING AND SEPARATION OF SOLID BODIES BY COMBINED Specification of Letters Patent.

Patented Dec. 13, 1921.

Application filed November 21, 1917. Serial No. 203,277.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT, L, 1313.)

To all whom it may concern:

Be it known that I, RENE EMILE TROTTIER, a citizen of the Republic of France, and resident of 84 Rue de la Rpublique, Puteaux, Seine, in the Republic of France, have invented a new and useful Process for the Classifying and Separation of Solid Bodies by Combined Action of Orientation, Deviation, and Derivation, (forwhich I have filed application in France, Feb. 29, 1916,) of which the following is a specification.

This invention consists in an improved process for the classifying and separation of solid bodies, according to which the particles to be separated are first classified simultaneously by equivalence and according to their shape, then submitted to the action of appropriate separating currents, determining successively the deviation and the regres sion or derivation of the particles according to their equivalence and their shape.

This improved process, utilizing simultaneously the difference of the form of the grains and their equivalence, permits the separation of substances of the same density and the same equivalence, but of different nature and form, and consequently a classi fication giving results superior to those obtaincd by methods hitherto used and dealing with the same substances being effected.

To render the following description clear,

it may be here stated that two bodies are termed equivalents when they sink in water at the same rate. By the term deviation is meant the action produced in a body falling in a fluid and resisting medium by an incidental force whose direction makes any angle with the vertical, the vertical component of this force being insufiiclent to reverse the direction of movement of the falling body and, consequently, smaller than that necessary to counterbalance the weight of the body, deduction being made for the volume of-water displaced. Finally, by the term derivation is meant the action produced under the above indicated conditions by an incidental force in a direction opposed to the vertical or making with the latter an angle less than 90, the vertical component of this force being sufficient to reverse the and consequently always greater than that necessary deduction being made for the volume of water displaced.

If there is thrown into a vessel, filled with still water, two grains of equal volume and density but of very different form, for example, one spherical and the other flat, the spherical grain falls vertically in a straight line, while the fiat grain follows a crooked line, or in other words tacks about or oscilates, vessel till after the spherical grain. On repeating this experiment after putting the water in motion from bottom to top, it will be found that the spherical grain, on the contrary, will reach the bottom of the vessel after the fiat grain if the plane of the greatest or effective section of the latter is substantially vertical. This is because the action of the current on the spherical grain is maintained constant, by reason of the effective section of such a grain remaining invariable; while the flat grain is immediately orientated or turned by the current in a manner to present to the current the section of least resistance. The fiat grain falls more slowly the nearer the position of its plane of gfeatest section approaches the horizontal p ane.

Thus, the speeds of descent of bodies in a fluid and resisting medium decrease as the ratio of their extreme dimensions, if the medium in which the fall occurs is at rest, and increase as this ratio and as the rate of flow of the medium when the medium is in movement and as the plane of the largest direction" of movement ofthe falling body,

section of the body approaches the vertical.

By interposing devices appropriate for deviation and derivation while these phenomena are produced, it should be possible to obtain an effective separation of the bodies according to their forms and quite independently of their density. Such is the basis of the present invention.

The accompanying drawing is a diagrammatic view of an apparatus for executing the V invention.

This apparatus comprises a vessel having to balance the weight of the body, I

and it does not reach the bottom of the diverging emptying channels 7 and 8, and

adjoining the latter is another channel 9.

Opposite plate 11, a duct 10 opens into the side wall of the vessel and conducts against the-lower face of the plate 11 water under pressure in a manner to set up an ascending current of water in passage 5, while a slight descending current is set up in the vessel by means of an adduction of water. The feeding in of the material to be classified is effected by means of a suitable distributor arranged at 12 above the level of the water and over the inclined wall 2. The compartment 6 isprovided with an overflow 13 and the passage 5 is also furnished with an overflow weir i l. 7

If, in apparatus thus arranged, sub-- stances which it is desired to separate be fed in at 12, after water is allowed to enter at 10, tie following will occur 'ln descending in the comparatively motionless water in compartment 6 the substances will become classified according to their equivalence and slide over the inclined portion of wall 2 and the plate 11; the round grains advance in front of the flat grains since the latter fall slower and are, moreover, retarded by rubbing on plate 11'. @n arrival at the bottom of plate 11 the lightest grains, incapable of traversing the. current of water issuing from the side duct 10, are immediately carried by the current into the passage 5 up to the ,level of the overflow, a, while the heavier grains, capable of traversing the current, fall toward the orifice of the outlet 7. The round grains, 'too light to reach outlet 7 but too heavy to reach overflow 14, rise. part way up the passage 5, then fall, sliding along wall 3 of the vessel and finally arrive at outlet 9, or they are thrown directly into 8 by deviation.

As to the fiat grains, which slide in rear of the round grains on the inclined surfaces 2, 11, lying on their large face, they are presented flatwise to the ascending current,

that is to say under conditions most un favorable for. traversing it and, retained in this position by the descending current in the vessel, they are diverted toward the passage 5 ;'the combined effect of the two currents is such as to turn them so that they present their smallest section to the flow of the water, and, consequently, fall,sliding along the outer wall 3 where the ascending current is slower than on the opposing wall 4, and finally arrive at outlet 9 where they are evacuated. v

Thus, the treated substances, be they very fine, granular or in fragmentaare classified in four categories. according to their form and density, viz:'

At outlet 7, heavy products or of high density (non-deviated);

. At outlet 8,.products of medium density, or mixed (deviated);

At outlet 9, wfiat products, ofany density (orientated) At overflow 14, light products, or of low equivalence (derived).

Moreover, if the substances are sedimentary, the fine particles in suspension are evacuated by the overflow 13in the compartment 6 of the vessel.

It goes without saying that when there is no disadvantage in mixing several kinds of products, the outlet ducts 8 and 9 can be combined in one or both can be omitted.

The apparatus above described is free from the faults found in the spitzkasten apparatus generally used for classifying by equivalence substances too fine for their volumetric. classification to be possible.

lln the improved system'of classified separation, as it will be seen, the particles, after submission to a classification by equivalence in still "water, are subjected to a second classification, according to their form, in

moving water, without any particle being able to remain in suspension at any moment, and the classifying is not perturbed as it is when spitzkasten are used. r:

In feeding the apparatus, the material is preferably diluted and thrown into the vessel intermittently so that the flat grains are not submitted at the same time as the round grains tothe action of the currents at the lower part'of the inclined plates 4 and 11. This however, is not indispensable. An oscillating screen of the kind described in United States Patent No. 1,074,301, September 30th, 1913, may conveniently be used for supplying the material to the vessel.

What I claim is: r

A process of the character described which includes the' following steps; first,

supplying the material into a substantially still classifying medium; second, obstructing the downward movement of the material by an inclined. surface; third, subjecting the -material, asit :passes off the said surface for the material which is able to pass through the upwardly moving current without being deviated thereby; fifth, providing In testimony that I claim the foregoing an upwardly extending outlet for the maas my invention, I have signed my name in terial which is freely carried along by the presence of two witnesses, this seventh dav upwardly moving current; and sixth, providof February, 1917. 5 ing an auxiliary downwardly extending outlet for the material which is unable to pass RENE EMILE TROTTIER. through the upwardly moving current when presented in one position to the said current Wltnessesi but is able to pass therethrough when pre- CHARLES ASH,

10 sented in another position to said current. CHAS. P. PRESSLY. 

